Fredericks effect

Erlick, C., and J. E. Frederick, Effects of Aerosols on the Wavelength Dependence of Atmospheric Transmission in the Ultraviolet and Visible. 2. Continental and Urban Aerosols in Clear Skies, J. Geophys. Res., 103, 23275-23285 (1998). 

Allen, M., and J.E. Frederick, Effective photodissociation cross sections for molecular oxygen and nitric oxide in the Schumann-Runge Bands. J Atmos Sci 39, 2066, 1982. 

In our view, all of the results of this experiment can be explained by the reorientation of the director in the electric field of the light wave, in analogy with the Fredericks transition. Fredericks transitions are observed in uniform, constant magnetic and electric fields. Our case is more complex, but the basic features of the Fredericks effect can be clearly seen. 

As was shown in Sec. 5, for certain types of liquid crystals the Fredericks transition can be accompanied by hysteresis. Let us calculate for the case of the well studied liquid crystal PAA the main characteristics of this phenomenon. As seen from formula (37) with B = -0.03 and G =0.06, the powers at which the Fredericks effect in PAA is switched on and off differ little Pn 0.992P,.. The angle corresponding to the appearance of a local minimum of the free-energy function [that is, (p corresponding to the inflection point of the function is [Pg.123]

Fig. 1 Field-driven director configurations in (a) a nematic liquid (conventional Fredericks effect) and (b) a nematic elastomer slab floating in liquid between rigid electrodes. They initially have a uniform planar orientation before imposing field E in the direction shown by the arrow. In (a), the director at the surfaces are anchored, and the rotation angle of director has a finite distribution along the field axis, with the maximum at the middle layer of the cell. The recovery force for the director originates from the Frank elasticity. In (b), the director is capable of uniform rotation under electric fields, and the Frank elasticity plays no role in the recovery force...

Bouton SN, Frederick PC, Spalding MG, McGiU HC. 1999. Effects of chronic, low concentrations of dietary methylmercury on the behavior of juvenile great egrets. Environ Toxicol Chem 18 1934-1939. 

Hoffman DJ, Spalding MG, Frederick PC. 2005. Subchronic effects of methyhnercury on plasma and organ biochemistries in great egret nestlings. Environ Toxicol Chem 24 3078-3084. 

Spalding MG, Frederick PC, McGill HC, Bouton SN, McDowell LR. 2000a. Methylmercury accumulation in tissues and its effects on growth and appetite in captive great egrets. JWildlDis 36 411 22. 

Rosenblatt, D.H. Dacre, J.C. Cogley, D.R. "An Environmental Fate Model Leading to Preliminary Pollutant Limit Values for Human Health Effects," Technical Report 8005, U.S. Army Medical Bioengineering Research and Development Laboratory, Fort Detrick, Frederick, MD, 1980, AD B049917L. 

Eaton JC, Young JY. 1989. Medical criteria for respiratory protection in smoke the effectiveness of the military protective mask. Frederick MD U.S. Army Biomedical Research Development Laboratory, AD-A204-303. 

Schaeffer DJ, Lower WR, Kapila S, et al. 1986. Preliminary study of effects of military obscurant smokes on flora and fauna during field and laboratory exposures. Frederick, MD U.S. Army Medical Bioengineering Research and Development Command. USA-CERL Technical Report N-86/22. 

John Frederick Helvetius (see plate 13), an eminent doctor of medicine, and physician to the Prince of Orange, published at the Hague in 1667 the following remarkable account of a transmutation he claimed to have effected. Certain points of resemblance between this account and that of van Helmont (e.g., in each case the Stone is described as a glassy substance of a pale yellow colour) are worth noticing "On the 27 December,... 

Cognitive and subjective effects The effects of LSD on attention have been examined in animal paradigms. LSD reduces accuracy on a multiple-choice reaction time task, which is reversed by a 5-HT2 antagonist (Carli and Samanin 1992). LSD produces gross alterations in time perception, which holds true in animal models as well as human reports (Frederick et al. 1997). 

Frederick DL, Gillam MP, Lensing S, Paule MG. (1997). Acute effects of LSD on rhesus monkey operant test battery performance. Pharmacol Biochem Behav. 57(4) 633-41. 

Army. 1984b. Database assessment of health and environmental effects of munition production waste products. Contract no. DE-AC05-849R21400. Frederick, MD U.S. Army Medical Research and Development Command, Fort Detrick. Document no. AD A145417. 

A study of the behavioral and neurochemical effects of the putative serotonergic neurotoxicant methylenedioxymethamphetamine (MDMA) or dexfenfluramine in rhesus macaques failed to reveal any effects on shortterm memory, motivation learning, and color and position discrimination (Frederick et al. 1995, 1998). 

Figure 3.25 shows the results of one set of calculations of the effects of aerosol particles whose properties were judged to be characteristic of continental or urban situations, respectively, on the transmission of UV and visible radiation to the earth s surface (Erlick and Frederick, 1998). The ratio of the transmission with particles to that without is plotted in two wavelength regions, one in the UV and one in the visible. Two different relative humidity scenarios are shown. The average summer relative humidity was 70% RH in the boundary layer and 20% RH in the free troposphere. The high relative humidity case assumes 90% RH in the boundary layer and 30% in the free troposphere. (The RH in the stratosphere was taken to be 0% in both cases see Chapter 12.)... 

Respiratory Effects. Lee and Frederick (1981) found that eye, respiratory, and skin irritation were among the complaints of 27/35 workers in a printing plant. Two of the workers (screen printers) were exposed to 8-hour TWA concentrations of isophorone of 0.7 and 14 ppm, but it was not clear whether these two individuals were among those who complained of respiratory irritation. Lee and... 

Abei, Sir Frederick Augustus(l827—1902), was a leading Brit scientist in the fields of propolis. and explosives. Introduced the practice of beating nitrocellulose to effect stabilization, devised a stability test for explosives which is named after him, and was the author of numerous patents and publications on explosives Refs 1)J.Spiller, JCS 87, 565-70(1905)... 

Erlick C., and Frederick J.E., Effects of aerosols on the wavelength dependence of atmospheric transmission in the ultraviolet and visible 2. Continental and urban aerosols in clear skies, J. Geophys Res., 103,23275-23285,1998. 

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